Estimating lifetime risk of diabetes in the Chinese population
Authors: Fiona Bragg, Zhengming Chen
Journal: PLoS Medicine (2022)

The worldwide epidemic of diabetes continues to grow [1].In China, the rise in prevalence has been notably rapid; about 12% of the adult population has diabetes [2], accounting for almost one quarter of cases worldwide [1] and representing a 10-fold increase over the last 3 to 4 decades.It is appropriate, therefore, that diabetes-both prevention and management-is a major focus of current health policy initiatives in China [3,4], and their success depends on reliable quantification of the burden of diabetes.Commonly used measures such as prevalence and incidence fail to capture excess mortality risks or differences in life expectancy in diabetes [5].Moreover, they may be less easily interpreted by policy makers and affected individuals.Estimates of lifetime risks and life years spent living with diabetes in an accompanying study by Luk and colleagues provide a valuable new perspective on the burden of diabetes in the Chinese population [6].The study used Hong Kong territory-wide electronic health records data for 2.6 million adults.Using a Markov chain model and Monte-Carlo simulations, Luk and colleagues estimated age-and sex-specific lifetime risks of diabetes (incorporating both clinically diagnosed and undiagnosed diabetes) and remaining life years spent with diabetes.Their findings showed a lifetime risk of 65.9% and 12.7 years of life living with diabetes for an average 20-year old with normoglycaemia.For an average 20-year old with prediabetes the corresponding estimates were 88.0% and 32.5 years, respectively.In other words, 6 out of 10 20-year olds with normoglycaemia and 9 out of 10 with prediabetes would be expected to develop diabetes in their lifetime.The estimated lifetime risks declined with increasing age and were higher among women than men at all ages, likely reflecting women's higher life expectancy.These estimated lifetime risks are striking and concerning.Moreover, they are notably higher than western population estimates [7-10], including those considering both diagnosed and undiagnosed diabetes [9,10].An Australian study estimated that 38% of 25-year olds would develop diabetes in their lifetime [10].Another study in the Netherlands reported 31.3% and 74.0%probabilities of developing diabetes in the remaining lifetime for individuals aged 45 years without diabetes and with prediabetes, respectively [9].Diabetes incidence and overall mortality influence population lifetime risks.Differences in the glycaemic indicators used to identify undiagnosed diabetes may have contributed to differences between studies in diabetes incidence.InAU : Anabbreviationlisthasbeencompiledforthoseusedinthetext:Pleaseverifythatall the study by Luk and colleagues, a combination of fasting plasma glucose (FPG), HbA1c levels and oral glucose tolerance testing (OGTT) was used, while in the Australian [10] and the Netherlands [9] studies, they used FPG/OGTT and mainly FPG, respectively.However, it is unlikely these differences would fully account for the large disparities seen in lifetime risk.Similarly, differences between life expectancy in Hong Kong (84.8 years), Australia (83.4 years), and the Netherlands (82.2 years) are too small to explain the differences.Interestingly, the high lifetime risks observed in Hong Kong were more comparable